Steam-engine valve



(No Model.)

D. D. HARDY.

STEAM ENGINE VALVE.

M. 1 F n. y. a d y w m.,

w@ ai ilnirnn 'Smarts Farmer Ormea.

DEXTER D. HARDY, OF CHICAGO, ILLINOIS, ASSIGNOR OF TW'O-TIIIRDS TOROBERT H. COVVDREY, OF SAME PLACE, AND MARY J. PERRY, OF DOWN- ERSGROVE, ILLINOIS.

STEAM-ENGINE VALVE.

SPECIFICATION forming part of Letters Patent No. 313,729, dated Marchl0, 1885.

Application filed May l0, 1834. (No model.)

To all whom it may concern.-

Be it known .that I, DEXTER D. HARDY, of Chicago, in the county of Cookand State of Illinois, have invented certain new and useful Improvementsin Steam-Engine Valves; and I do hereby declare that the following is afull, clear, and exact description thereof, reference being had to theaccompanying drawings, and to the letters of reference marked 1othereon, which form a part of this specification.

This invention relates to an improved construction in steam-valves forengines. Itembraces an improved construction in balanced slide-valvesfor controlling the cylinder-ports of a steam-engine, 'and also animprovement in reversing-valves adapted for use either with the balancedvalve mentioned or with other forms of steam-valves; and it consists inthe 2o matters hereinafter described,and pointed out in the claims.

In the accompanying drawings, Figures l and 2 are central longitudinalsectional views of an engine-cylinder illustrating my invention. Fig. 3isahorizontal sectiontaken upon line .fr :o of Fig. l.` Fig. 4 is ahorizontal section taken upon line 1/ y of Fig. 1. Fig. 5 is a verticalsection taken upon line a e of Fig. 2.

As shown in the accompanying drawings,

A is an engine-cylinder, having a piston, B, and piston-rod C, ofordinary construction.

D is a steam-chest, which is provided with opposite parallel planesurfaces forming valveseats D and D2, the valve-seat D', as hereinshown, being adjacent to the cylinder, and provided with ports f f,communicating with the ends of the cylinder by means of passages F F, inthe usual manner.

Within the steam-chest D is a centrally- 40 open or hollow slide-valve,E, which is operated by means of a valve-rod, e, passing through anordinary stuffing-box, d, in the wall ofthe steam-chest D. The saidvalveis,

as herein shown and preferably constructed, Vrectangular in form, andnarrower than the space between the side walls of the steamchest, so asto permit the passage of steam around it from one end to the other ofthe said steam-chest, and is constructed to bear at its edges upon theopposite valve-seats, D and 5o D2, of the steam-chest.

G and H are steam inlet and exhaust passages, communicating with thesteam-chest in its portion inside of and exterior to the slidevalve. Theports f f are arranged at the same 5 5 distance apart as the transverseend pieces, E', of thervalve E; and the said valve operates, inconnection with said ports, to admit steam alternately to the oppositeends of the cylinder in a well-known manner. The'bearingsurfaces uponthe opposite side of the valve E are preferably made of the same width,so that the area of such surface in contact with each ofthe valve-seatsD and DI is the same, and the steam-pressure upon the valve will therebybe perfectly balanced. The Valve E is preferably provided at one of itsedges with a separate part or strip, e', which is held outwardly incontact with the valve-seat by means of metal or other springs, so as toform a packing, in a well-known manner. The same effect will obviouslybe produced by permitting the entrance of steam between the parts of thevalve, so as to press said parts against the opposite valve-seats, thusforming what is known as a steam-packing.77 The valve E is, as hereinshown,held between guides d d', formed upon the opposite surfaces of thesteam-chest adjacent to the valve-seats. The said valve may, however, beotherwise held and guided, as may be found convenient or practicable,and the particular form of guides shown are not essential to theopera-tion of the valve.

I is a valve-chamber, with which the paS- sages G and H, leading fromthe steam-chest, communicate, and which may be located upon the saidsteam-chest, as herein shown, or elsewhere, or at a distance therefrom,as found desirable. The said valve-chamber I is connected with suitablesteam-inlet pipes, L, leading from the steam-generator, and is providedwith an exhaust-pipe, M, for the exit of steam therefrom. The passages Gand H, which conneet the steam-chest with the valve-chamber 95 I,terminate within the latter chamber in ports g h, and within saidchamber I is located a slide-valve,IC, which is generally similar ininlet L or exhaust-passage M into communication with the passages G orH, as hereinafter more particularly described. 'Ihe valve K is, lasshown, of rectangular form, and provided with four walls iitted at theiredges'to lthe op-V posite plane faces of the chamber, spaces being leftbetween the sides of the valve and the side walls of the chamber, asclearly shown in Fig. 5, to permit the passage of steam from one end pfthe chamber to the other around the valve. The said valve is, as hereinshown,

operated by means of a valve stem or rod, k,

.passing through a suitable stuffing-box, c', in

`the wall of the chamber I, and its transverse end portions, K, arelocated at the samedistance apart as the ports g and h of the passages Gand H, so that when the valve is moved a distance equal to the width ofone of the ports, plus the thickness of one of the parts K', the portswill be brought inside or outside ofthe valve in a well-known manner.The guides t" t" are, as herein shown, formed upon the opposite parallelfaces ofthe valve-chamber I, between which guides the valve K isarranged to slide; but any other well-known means of supporting the saidvalve may obviously be used in connection with the form of valveillustrated. rlhe valve K is preferably provided with a separate pieceorpacking-strip, k', similar to that before described in connection withthe valve E, and the said valve, having equal opposite bearing-surfaces,as before set forth, in connection with said valve E, is also perfectlybalanced with reference tosteam-pressure tending to force the valveagainst its seatin either direction. The inlet-pipe L enters thevalve-chamber I in its central portion and communicates with the spaceof the chamber within the hollow valve K, and the exhaust-pipe Mcommunicates with the portion` of the chamber exterior to the valve, thesaid inlet and exhaust pipes being so arranged that they are unaffectedby the movement of the valve, which operates upon the ports g and honly.

rIhe effect of changing the position of the valve K with reference tothe ports is obviously to reverse the course of the'steam through thepassages G and H, and thereby change the direction of motion of theengine, as will be rendered clear by an inspection of Figs. 1 and 2 ofthe accompanying drawings, in which the valve K is shown in the twopositions taken by it at the opposite limits of its throw.

In Fig. 1 the reversing-valve K, above referred to, is shown inposition, with the passage Gin communication with the space within theinterior of the valve K, and the passage H in communication with thespace of the valve-chest exterior to the said valve, so that passage isafforded for steam from the inletpipe L, which opens into the interiorspace of the valve through the said passage G to the steam-chest, andalso from the passage H to the exhaust-passage M. In this case thepassage G obviously forms the steam-inlet to, and thepassage H theexhaust-passage from, the steam-chest.

In Fig. 2 the valve K is shown at the opposite end of its throw fromthat yshown in Fig. 1, the inlet-passage L being in this case incommunication with the passage H, and the exhaust-pipe M incommunication with the passage G, so that the passage G has become theexhaust-passage of the steam-chest, and passage H the inlet passagethereto. The slide-valve E is shown in the same position in both figuresmentioned, and the course of the steam by arrows. f

It is obviously immaterial to the operation of the valves E and K as tothe points at whichl the inlet and exhaust passages enter t-hesteamchest and valve-chamber, it only being necessary in either casethat one of the passages communicate with the interior space of thevalve, and the other with the space of the valve chest or chamberexterior thereto. The said passages may, for instance, enter the valvechest or chamber at the side thereof opposite to that at which they areshown as entering it, in the same manner that the steam inlet andexhaust passages used in connection with an ordinary D-valve usuallyenter the The reversing-valve described is especially valuable asapplied to locomotive-engines, for

I IO

the reason that by its use the link vreversing' gear heretofore used insuch engines, whichis objectionable on account of its weight and costand the force required to operate it, may be dispensed with.

It is obviously possible to use any kind of steam-valve for controllingthe cylinder-ports in connection with the reversing-valve described,instead of the balanced slide-valve herein shown; and it is also obviousthat any suitable form of slide-valve may be used as a reversing-valvein place of the balanced valve shown-as, for instance, an ordinaryD-valve. I do not therefore limit myself to a construction in which thereversing-valve is used in 4combination with the balanced slide-valveshown, except in the claims, in which such combination is expressed; nordo I limit myself to the exact features of construction inV thereversing-valve or the steam-valve herein illustrated, except in theclaims, in which such features of construction are set forth.

y I claim as my inventionl. The combination, with a steam chest and IISISO

Valve of anv engine, of an auxiliary valvecharnber having oppositeparallel valve'seats, and ports communicating with the steamehest, acentrallyopen slide-valve in said eharnDer, constructed to operate inconnection with the opposite Valve-seats, and steam inlet and exhaustpipes communicating with the portion of the valve-chamber Within theslide* valve, and with the space of the Valve-chamber exterior to saidvalve, substantially as and for the purpose set forth. i

2. The combination, with the cylinder of asteani-engine, of asteam-chest having opposite parallel valve-seats,a centrally-openslidevalve operating in Contact With the opposite Valve-seats of saidsteamehest7 suitable steampassages connecting the steanrehest with theCylinders7 an auxiliary valveehaniber having opposite parallelvalve-seats, and ports Communicating with the portion of the steam-chestWithin the slide-valve, and with the space of the steam-chest exteriorto the valve, a oentrally open slide valve Within said valveeliamloer,constructed to operate in contact With the opposite valve-seats of thesaid valveehaniloer, and steam inlet and exhaust pipes communicatingwith the space of the valveehamber inelosed by the slide-valve, and withthe space of the chamber exterior to said retaining the said Valve inposition, substantially as described. v

In testimony that I claim the foregoing as my invention I affix mysignature in presence of two Witnesses.

DEXTER D. HARDY.

Witnesses:

M. E. DAYTON, Jnssn COX, Jr.

